Development and functionality analysis of lipoplex-loaded polysaccharide-based surface coatings for local nucleic acid delivery

Although therapeutic nucleic acids reached the clinical application for a decade, the success of these new drugs is dependent on their delivery strategies, which are still a challenge. In particular, local delivery of nucleic acids is a promising approach to develop therapies with a spatially controlled site of action. However, compared to techniques for systemic administration, local nucleic acid delivery systems are still rarely described. In this study, we present a promising approach to fill this gap by the design of surface coatings based on polysaccharides for local delivery of nucleic acids. An automatized Layer-by-Layer deposition approach was applied using hyaluronic acid and chitosan to form polyelectrolyte multilayer systems, into which lipid nanoparticles, more specific lipoplexes, were embedded as nucleic acid carriers. Different manufacturing parameters, in particular the number of deposited polyelectrolyte layers and the preparation buffer, were varied. The multilayer film characteristics were investigated systematically regarding their physical properties, with a focus on thickness and topology as well as lipoplex deposition, to identify a system with efficient transfection properties. The multilayer systems prepared in acetate buffer were characterized by a good lipoplex embedding with a more uniform distribution and lower tendency for formation of large lipoplex aggregates in the polyelectrolyte film. Additionally, we were able to demonstrate the functionality of the developed system for nucleic acid delivery. The nucleic acids were successfully transferred into cells in a contact-triggered manner. Furthermore, we could demonstrate the enzymatic degradation-based release of nucleic acid cargo from the delivery system caused by hyaluronidase, followed by successful in vitro transfection

Concurrent CDX2 cis -deregulation and UBTF::ATXN7L3 fusion define a novel high-risk subtype of B-cell ALL

Oncogenic alterations underlying B-cell acute lymphoblastic leukemia (B-ALL) in adults remain incompletely elucidated. To uncover novel oncogenic drivers, we performed RNA sequencing and whole-genome analyses in a large cohort of unresolved B-ALL. We identified a novel subtype characterized by a distinct gene expression signature and the unique association of 2 genomic microdeletions. The 17q21.31 microdeletion resulted in a UBTF::ATXN7L3 fusion transcript encoding a chimeric protein. The 13q12.2 deletion resulted in monoallelic ectopic expression of the homeobox transcription factor CDX2, located 138 kb in cis from the deletion. Using 4C-sequencing and CRISPR interference experiments, we elucidated the mechanism of CDX2 cis-deregulation, involving PAN3 enhancer hijacking. CDX2/UBTF ALL (n = 26) harbored a distinct pattern of additional alterations including 1q gain and CXCR4 activating mutations. Within adult patients with Ph- B-ALL enrolled in GRAALL trials, patients with CDX2/UBTF ALL (n = 17/723, 2.4%) were young (median age, 31 years) and dramatically enriched in females (male/female ratio, 0.2, P = .002). They commonly presented with a pro-B phenotype ALL and moderate blast cell infiltration. They had poor response to treatment including a higher risk of failure to first induction course (19% vs 3%, P = .017) and higher post-induction minimal residual disease (MRD) levels (MRD ≥ 10-4, 93% vs 46%, P < .001). This early resistance to treatment translated into a significantly higher cumulative incidence of relapse (75.0% vs 32.4%, P = .004) in univariate and multivariate analyses. In conclusion, we discovered a novel B-ALL entity defined by the unique combination of CDX2 cis-deregulation and UBTF::ATXN7L3 fusion, representing a high-risk disease in young adults

Concurrent <i>CDX2 cis</i>-deregulation and <i>UBTF::ATXN7L3</i> fusion define a novel high-risk subtype of B-cell ALL

Abstract Oncogenic alterations underlying B-cell acute lymphoblastic leukemia (B-ALL) in adults remain incompletely elucidated. To uncover novel oncogenic drivers, we performed RNA sequencing and whole-genome analyses in a large cohort of unresolved B-ALL. We identified a novel subtype characterized by a distinct gene expression signature and the unique association of 2 genomic microdeletions. The 17q21.31 microdeletion resulted in a UBTF::ATXN7L3 fusion transcript encoding a chimeric protein. The 13q12.2 deletion resulted in monoallelic ectopic expression of the homeobox transcription factor CDX2, located 138 kb in cis from the deletion. Using 4C-sequencing and CRISPR interference experiments, we elucidated the mechanism of CDX2 cis-deregulation, involving PAN3 enhancer hijacking. CDX2/UBTF ALL (n = 26) harbored a distinct pattern of additional alterations including 1q gain and CXCR4 activating mutations. Within adult patients with Ph− B-ALL enrolled in GRAALL trials, patients with CDX2/UBTF ALL (n = 17/723, 2.4%) were young (median age, 31 years) and dramatically enriched in females (male/female ratio, 0.2, P = .002). They commonly presented with a pro-B phenotype ALL and moderate blast cell infiltration. They had poor response to treatment including a higher risk of failure to first induction course (19% vs 3%, P = .017) and higher post-induction minimal residual disease (MRD) levels (MRD ≥ 10−4, 93% vs 46%, P &amp;lt; .001). This early resistance to treatment translated into a significantly higher cumulative incidence of relapse (75.0% vs 32.4%, P = .004) in univariate and multivariate analyses. In conclusion, we discovered a novel B-ALL entity defined by the unique combination of CDX2 cis-deregulation and UBTF::ATXN7L3 fusion, representing a high-risk disease in young adults.</jats:p